Hepatitis B previously had no antibodies and now have antibodies, there are two cases, one is vaccinated against hepatitis B, the other is infected with the hepatitis B virus in the recovery period. 1. After receiving hepatitis B vaccine, the body can produce immune response and generate protective antibody against hepatitis B, which is the main means of preventing hepatitis B infection. 3 doses of hepatitis B vaccine are required in the vaccination program, 1 month after the first dose of vaccination, the second dose is given at an interval, and the third dose is given at an interval of 5 months, and the antibody test can be performed 1 month after the completion of the vaccination. 2. infected with hepatitis B virus, patients infected with hepatitis B virus, the body’s immune system to play a role in clearing the virus, or after regular treatment of hepatitis B virus is cleared by the body, the production of protective antibodies hepatitis B surface antibody, usually accompanied by hepatitis B core antibody is positive, the patient can be further HBV-DNA test to make clear, or consult the physician’s guidance. Hepatitis B surface antibody is positive is good, the body has a protective effect, can prevent the infection of hepatitis B. We recommend that the patient regularly recheck the two half of hepatitis B and other indicators, consult with a physician, if necessary, hepatitis B vaccination.